Exchange not recieving any emails.

I am getting errors on all mail inbound, and nothing is going through exchange internally either. I get errors from inbound mail. NDR reports 5.0.0. I also get a message from the postmaster, rfc822 username, action failed, status 5.0.0.
I have been going through SMTP changes all morning trying to fix this, but it was working yesterday and up till around 7 am.

Uninstall any antivirus/spam software you have in the server then reboot.
Follow these instruction internally to do a telnet test: http://support.microsoft.com/kb/153119
If that works goto http://whatsmyip.org

SMTP and recipient policy are as you said. I tried the 'send from' again using an internal user as the from address. I did it before with an external address.
I get 'unrecognized command' when i try an internal address. I tried using 'Admin", and it told me bad address.

I am telnetting internally. Internal emails do not work either, as in two users from the organization. It was working yesterday. I am converting people to exchange from a non-exchange environment. The last user was converted yesterday, and when i came in i had planned on working on getting thier phones working with exchange.
Instead, all emails from all of their customers are getting bounced.

Do your employees use mobile devices to reply to emails? With mobile becoming increasingly important to the business world, it is in your best interest to make sure that your email signature looks great across all types of devices.

I have a POP3 connector going to the old email server at their web hosting provider, i see the mail come in there, i see it get transferred to the exchange server, and then the exchange server checks kicks it back.
I can send emails all day from any user.

Why would this have worked perfectly all night, and then today it is hosed for everyone? I set up the first users last week, and finished yesterday.
I ran the best practices analyzer, and nothing. I can see some spam type messages stacking up in the queue, and when i send from outside the organization it apparently gets kicked back before it sits in the queue for more than a second.

AArrrrgghhh. After talking with y'all, and still searching portions of the error, Microsoft came out with the fix.
Windows POP3 services were running, which are in conflict with Exchange POP3 services. I rebooted this morning, had breakfast and a shower, made the long drive in and started working on the problem. When i rebooted, the service must have started, killing all inbound mail.

Thanks a bunch guys. I feel about 20 pounds lighter and would love to buy you all a drink.

Featured Post

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

In this video we show how to create a mailbox database in Exchange 2013. We show this process by using the Exchange Admin Center.
Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center.
Navigate to the Servers >> Data…

The basic steps you have just learned will be implemented in this video. The basic steps are shown to configure an Exchange DAG in a live working Exchange Server Environment and manage the same (Exchange Server 2010 Software is used in a Windows Ser…